A furious Bronx state assemblywoman yesterday shouted down the family of 7-year-old Nixzmary Brown, publicly rebuking relatives for not taking responsibility for the child’s murder.

The murder of the little girl – allegedly by her stepfather as her mother stood by – stunned the city and prompted a shakeup of the Administration for Children’s Services after it was learned agency workers missed several chances to save her.

The verbal fireworks broke out at an Assembly hearing in lower Manhattan into how the child’s tragic death could have been prevented.

Nixzmary’s grandmother and her spokeswoman made an unscheduled appearance and lambasted the ACS for keeping Nixzmary’s siblings in foster care.

“ACS failed Nixzmary and we want you to know,” Awilda Cordero, the family spokeswoman, testified as grandmother Maria Gonzalez looked on.

“She died and now the grandmother is left behind trying to fight for custody of the other kids and no one is here to help her,” Cordero said.

“The foster mother is getting a nice check.”

At that point, a fuming Naomi Rivera (D-Bronx) interrupted her.

“I want to remind you that the first adults to neglect Nixzmary were the family, then ACS,” she said. “So if you would like to open up, if you’re prepared to answer several questions, then maybe we can.”

As the women engaged in an angry back-andforth, the chairman of the Committee on Children and Families, William Scarborough (D-Queens) interrupted:

“God bless you and thank you very much,” he told the family members, who stepped down from the witness stand but remained at the hearing.

Afterward, Rivera explained her fury: “Yes, ACS is broken. It needs fixing. It is certainly responsible but the responsibility starts at home. And the family failed little Nixzmary. I felt the need to make that very clear.”

The tension didn’t dissipate when ACS Commissioner John Mattingly was put on the hot seat.

He said the future of Nixzmary’s siblings would be decided in Family Court after an investigation.

Meanwhile, three Bronx lawmakers called for Mattingly’s head, saying the reforms should start with his dismissal.